Method of making a slug having controlled grain direction

ABSTRACT

A metal slug having an improved grain orientation wherein the individual grains thereof are in substantially parallel relation; and, a method of making such a slug from an inexpensive wrought rod without waste wherein the grain orientation of a rod blank from which the slug is made is altered to provide the completed slug having the improved grain orientation.

United states Patent [1 Dew et al.

[ METHOD OF MAKING A SLUG HAVING CONTROLLED GRAIN DIRECTION [75]Inventors: Rudolph V. Bew; Anderson J.

Walters; Donald J. Funk; Joseph R. Frazier, Jr., All of Richmond, Va.

[73] Assignee: Reynolds Metals Company,

[58] Field of Search 72/377, 356, 339; 29/183 [56] References CitedUNITED STATES PATENTS 2,064,323 12/1936 Schmidt et al 72/377 5/1966Spyridakis 72/377 X 3,250,109 3,595,058 7/1971 Beneke 72/339 FOREIGNPATENTS OR APPLICATIONS 666,354 7/1963 Canada 29/183 Primary Examiner-A.B. Curtis [5 7 ABSTRACT A metal slug having an improved grainorientation wherein the individual grains thereof are in substantiallyparallel relation; and, a method of making such a slug from aninexpensive wroughtrod without waste wherein the grain orientation of arod blank from which the slug ismade is altered to provide the completedslug having the improved grain orientation.

2 Claims, 16 Drawing Figures PAIENIEBums m4 3844.155

snttnnr 3 THEIR ATTORNEYS Pmmtnum 29 am 3; -s|m2or a 844155 FIG-5INVENTORS RUDOLPH V. BEW ANDERSON J. WALTERS DONALD J. FUNK JOSEPH R.FRAZIER,JR.

' V THEIR ATTORNEYS METHOD OF MAKING A SLUG HAVING CONTROLLED GRAINDIRECTION BACKGROUND OF THE INVENTION It has been found very economicalto make extruded articles using metal slugs produced from elongated rodstock. However, these slugs generally tend to have weak spots which aredue to the comparatively poor grain orientation of such slugs wherebythe occurrence of these weak spots introduces additional inspectioncosts and scrap costs which tend to reduce the inherent cost advantagesof producing slugs from such rod stock.

SUMMARY This invention provides a metal slug having an improved grainorientation wherein the individual grains thereof are in substantiallyparallel relation. Further, this invention provides an improved methodof making such a slug without waste and from an inexpensive rod blank byaltering the rod blank from which the slug is made to produce thedesired grain orientation.

Other details, uses, and advantages of this invention will becomeapparent as the following description of the exemplary embodimentsthereof presented in the accompanying drawings proceeds.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings show presentpreferred embodiments of this invention, in which FIG. I is afragmentary view of an elongated substantially right circular.cylindrical rod which may be severed or cut essentially as shown by thedotted Iinesillustrated to define a plurality of rod blanks each ofwhich may be altered in accordance with the teachings of this inventionto define an improved slug particularly adapted to be used in makingarticles therefrom by extrusion;

FIG. 2 is a view in elevation with parts broken away and parts shown bydotted lines of an exemplary press having a pair of cropping dies whichmay be used to sever the elongated rod of FIG. 1 and define rod blanks;

FIG. 3 is a fragmentary cross-sectional view illustrating an exemplaryforming apparatus which may be utilized to partially form the rodblanks;

FIG. 4 is a perspective view of a partially formed rod blank which hasbeen formed by the apparatus of FIG. 3;

FIG. 5 is a fragmentary cross-sectional view illustrating anotherexemplary apparatus which may be used to finally form the partiallyfonned blank of FIG. 4 after placing such blank in position so that itspredominant grain direction is arranged transverse the direction offorming movement of the apparatus and showing such apparatus at thebeginning of the forming movement;

FIG. 6 is a view similar to FIG. 5 illustrating the apparatus of FIG. 5at the completion of the forming movement;

FIG. 7 is a perspective view of the completed slug after removal fromthe forming apparatus;

FIG. 8 is a cross-sectional view taken on the line 8-8 of FIG. 7 showinga plurality of spaced dotted lines arranged in parallel relation toindicate the arrangement of the grains in the finished slug of FIG. 7;

FIG. 9 is a perspective view of an exemplary article in the form of ashell casing formed by impact extrusion using a slug made in accordancewith this invention;

FIG. 10 is a perspective view of an elongated rod of rectangularcross-sectional configuration which may be used to make rod blanks eachhaving the shape of a parallelepiped and each being used to define animproved slug in accordance with this invention;

FIG. 11 is a fragmentary cross-sectional view of a forming apparatuswhich may be used to partially form a rod blank of rectangular crosssection after placing such blank in its forming position with itspredominant grain direction arranged transverse the direction of formingmovement and showing such apparatus at the beginning of the formingmovement;

FIG. 12 is a view similar to FIG. 11 and showing the apparatus of FIG.10 at the completion of the forming movement;

,FIG. 13 is a perspective view of a partially formed rod blank as formedby the apparatus of FIG. 12;

FIG. 14 is a fragmentary cross-sectional view of another fonningapparatus similar to the apparatus shown in FIGS. 11 and 12 which isused to finally form the partially formed blank of FIG. 13 and showingsuch apparatus at the completion of its forming stroke with the finallyfonned slug in position therein; and

FIGS. 15 and 16 are fragmentary cross-sectional views of an apparatusand method for forming a rod blank to define a completed slug in onestep without first partially forming the rod blank.

DESCRIPTION OF ILLUSTRATED EMBODIMENTS Reference is now made to FIG. 1of the drawings which illustrates one exemplary embodiment of anelongated wrought rod of circular cross-sectional configuration whichhas a predominant grain direction which is substantially parallel to thelongitudinal axis thereof. The rod 20 is suitably cut as indicated by aplurality of dotted lines 21 to define rod blanks 22 of substantiallyright circular cylindrical configuration which may be used to make theimproved slug of this invention, and in a manner to be described indetail subsequently. I

Any suitable means may be utilized to sever the elongated rod 20 todefine blanks 22; however, in this example of the invention the severingaction is achieved in a press 23 of conventional construction which hasa pair of cooperating cropping dies 24 and 25. The rod 20 is fed intothe press 23 utilizing any suitable technique whereupon the croppingdies 24 and 25 sever the rod to define rod blanks 22 which are conveyedby a gravity chute 26 into a container 27. The cropping dies sever therod 20 in a precise manner so that each rod blank 22 has a preciselength or height and hence an exact weight. It will also be appreciatedthat suitable control devices may be provided in the press 23 to adjustthe length of rod blanks 22 severed by dies 24 and 25, as desired.

The rod blanks 22 are formed to define a substantially disc-like slugwhich is illustrated in FIG. 7 of the drawings and designated generallyby the reference numeral 30 and the slug 30 has a smooth exterior whichis free of projections such as burrs, ears, flashings, or

the like. The slug 30 is particularly adapted to be used in extruding anarticle therefrom by known impact extrusion techniques and FIG. 9illustrates an exemplary shell 31 for a projectile which is made byimpact extrusion using a slug 30.

Inasmuch as the elongated rod from which each rod blank 22 is made has apredominant longitudinal grain direction, as previously mentioned, itwill be apparent that each blank 22 also has a corresponding predominantgrain direction. The blank 22 may be supported on a forming apparatus orpress 33, see FIG. 3 which illustrates a portion of press 33, andpartially formed to define a partially formed blank 34 which isillustrated in perspective view in FIG. 4.

The press 33 may be of conventional construction whereby only a portionthereof has been illustrated. The press 33 comprises a die assembly ordie 35 having an outer member 36 provided with a cylindrical surface orbore 37 and an inner member 40 which may be axially moved within thebore 37. The inner member has an outside surface 41 which cooperateswith the surface 37 to define a die cavity 42. The press 33 has a punchor ram 43 which is movable toward and away from the die 35 to enableforming of a rod blank 22 placed in the die cavity 42.-

The blank 22in this example is substantially longer than the widthacross the die cavity 42 and is supported within such cavity so that itspredominant grain direction, indicated by a double arrow 44, is arrangedsubstantially parallel to the direction of forming movement of the press33 and in particular its ram 43. The blank 22 is then partially formedand after this partial formformed blank 34 are rounded as illustrated at46 whereby undesirable flashing is prevented upon subsequently upsettingthe blank 34, see FIGS. 3 and 4, and the vertical height of such blankis substantially reduced by an amount indicated at 47.

The partially formed blank 34 is then placed in a second formingapparatus or press 50 (see FIG. 5) so that its predominant graindirection 44 is arranged transverse the direction of forming orimpacting, also preferably referred to hereinafter as upsetting,movement of the press 50. The press 50 is similar to the press 33 andmay also be of conventional construction whereby only a portion thereofhas been illustrated in FIGS. 5 and 6. The press 50 has a die assemblyor die 51 comprised of an outer stationary die portion 52 provided witha cylindrical bore or surface 53 and a movable inner portion 54 which issupported within the bore 53 and has an outside surface 54A whichcooperates with the outer portion of the bore 53 to define a cavity 55.The press 50 also has a punch or ram 56 which has an inwardly concavesurface 57 surrounded by a planar surface 60 and the purpose of thesurface 57 will be described in detail subsequently.

The partially formed blank 34 is placed within the cavity 55,50 that itspredominant grain direction 44 is arranged transverse the direction offorming movement provided by the press 50 and in the illustration ofFIG. 5 the predominant grain direction is shown arranged horizontally.The ram 56 and die 51 are then relatively moved together in a high speedforceful manner to impact and thus upset the partially formed blank 34and define the completed slug with the impacting or upsetting movementbeing terminated once surface 60 of ram 56 engages a cooperating surface61 on the outer member 52 of die 51.

Once the upsetting action has been completed, as shown in FIG. 6, themovable member 54 of die 51 may be moved outwardly relative to the outermember 52 and serves as a knock-out device for removing the completedslug 30 from within the cavity 55. Upsetting the partially formed rodblank 34 to define the completed slug 30 improves its grain orientationand in particular the upsetting serves to align the individual grains,or what is oftenv referred to as the grain flow direction, of the metalblank so that the individual grains are substantially perpendicular tothe direction of upsetting movement provided by relatively moving theram 56 and the die 51 together whereby in the completed slug '30 thegrains are substantially parallel as illustrated by dotted lines 62 inFIG. 8 of the drawings.

In this example of the invention the workpiececontacting surface 57 hasan inwardly concave configuration which results in the forming of acorresponding convex surface 63 on the slug 30. However, it will also beappreciated that either or both surfaces 54A and 57 may be suitablyshaped to define a corresponding outside surface of the completed slug30, as desired.

Thus, it is seen that an elongated metal rod 20 may be severed to definea plurality of rod blanks 22 which are first partially formed in aforming apparatus such as a press 33 to define a partially formed blank34. The partially formed blank 34 is then finally formed in a formingapparatus or press 50 to define the completed slug 30 having a granularorientation which makes it particularly adapted to be used to provideextruded articles such as by impact extrusion, for example.

As previously indicated, the presses 33 and 50 may be of conventionalconstruction and operation and each may upset .its associated workpiecesby either gradual or impacting movements with impacting movements beingpreferred. Further, it will be appreciated that in each press either theram or die assembly or both may be suitably resiliently supportedutilizing mechanical springs, rubber mounts, or the like to assure thatthese components will not be damaged during upsetting movements.

The improved slug 30 may also be made from an elongated rod which has anon-circular (such as, rectangular, for example) cross-sectionalconfiguration, see FIG. 10, which for ease of presentation andcorrelation with the description of rod 20 will be designated by thereference character 20A. The rod 20A may be severed along lines 21Autilizing any suitable technique, such as the punch press 23 illustratedin FIG. 2 and described in connection with the severing of the rod 20,to define a plurality of rod blanks 22A and reference may be made to theprevious description for an understanding of the operation of the press23.

The rod 20A is a wrought rod and has a predominant grain direction whichis parallel to its longitudinal axis. However, because of therectangular cross-sectional configuration of the rod 20A, the rod blanks22A are cut so that they have the general shape of a parallelepiped andin this example the parallelepiped is in the form of a cube. As in thecase of the rod 20, the severing action is preferably achieved bycutting the blanks 22A so that each has an exact weight whereby uponupsetting each blank 22A in a suitable forming apparatus a final slug isdefined, which is substantially identical to the slug illustrated inFIG. 7 and such final slug has been given the same reference numeral 30.

The main advantage of utilizing the rod blank 22A is that instead ofpartially forming the blank 22A to substantially reduce the heightthereof as was required in the case of the rod blank 22, it is possibleto provide the forming action with the grain direction properly orientedand without first reducing the height of the blank. In particular, theblank 22A may, at the outset, be placed in an associated formingapparatus or press with its predominant grain direction 44A arrangedtransverse the direction of forming movement of the press, see FIG. 11.The press of FIG. 11 is very similar in construction (except for itsram) and operation to the press 33 hence, for ease of description, itwill be given the identical reference numeral 33 and components thereofwill be given the same reference numerals as corresponding components ofthe previously described press 33.

The blank 22A is partially formed by relatively moving the cooperatingram 43 and die 35 from the position of FIG. 11 to the position of FIG.12 to effectively round certain corners of the blank 22A, and define thepartially formed blank 34A having only its upper corners, which aredesignated by the reference numerals 46A, partially rounded. Thispartial rounding of the upper corners assures that upon finally formingthe blank 34A the final slug will have the desired grain orientation aswell as a smooth exterior free of projections such as burrs, and thelike, in the manner previously described; and, any tendency for flashingto form on the finally formed slug is substantially eliminated.

In this latter exemplary embodiment of the invention, only the topcorners 46A of the partially formed blank 34A have been rounded in thepress 33; however, it will be appreciated that in some applications ofthis invention it may be desirableto round all corners of the severedrod blank 22A to assure the final slug 30 has the desiredcharacteristics.

The partially formed blank 34A is then placed in another formingapparatus or press which is substantially identical to the pressillustrated in FIG. 5 and the fragmentary portion of the pressillustrated in FIG. 14 will be designated generally by the referencenumeral 50 and its component parts will be designated by the samereference numerals as corresponding component parts of the press 50previously described whereby the detailed construction and operation ofpress 50 will not be repeated.

The partially formed blank 34A is placed in the press 50 so that itspredominant grain direction 44A is again arranged transverse thedirection of forming movements of such press and as in the case of blank34 the final forming of blank 34A is provided by forcefully upsettingthe blank 34A to define the completed slug 30 which has an outerappearance and a grain orientation as illustrated in FIGS. 7 and 8respectively of the drawings, and as previously described.

From the above description it is apparent that a slug particularlyadapted for extrusion may be defined from an elongated rod irrespectiveof the cross-sectional configuration of such rod and that the elongatedrod blanks are first partially formed in one apparatus or press 33 andthen finally formed in another press 50. However, it will be appreciatedthat, depending on the detailed dimensions of the final slug andcross-sectional characteristics of the elongated rod employed, it isentirely possible to form a final slug in a one-step operationessentially as shown in FIGS. 15 and 16.

For example, a rod blank 65 may be suitably cut from an associated rodand placed in the press 50 with its predominant grain direction arrangedperpendicular to the direction of forming movement whereupon the ram 56may be moved or impacted forcefully against the blank to define thecompleted slug 30, as shown in FIG. 16, so that the grains are arrangedin substantially parallel relation and in a direction substantiallyperpendicular the direction of impacting movement of the press 50.

In the above description of presses 33 and the die assembly in eachinstance has been described as being stationary with the ram beingmovable relative thereto. However, it is to be understood that eitherthe ram or its associated die or both may be movable to provide thedesired forming or upsetting movement such as impacting, for example.

It is well known that wrought rods formed by mechanical action such asby extrusion, for example, may be manufactured comparativelyinexpensively. Further, the slugs formed from wrought products generallyproduce the best extruded articles. This invention enables the provisionof an inexpensive high quality slug and a method of providing such aslug which enables an inexpensively produced rod to be utilized withoutwaste material and without sacrificing the quality of the slug and henceof the final article extruded therefrom in a manner heretofore unknown.

The elongated rods 20 and 20A used to make the rod blanks 22 and 22Arespectively from which the improved slugs 30 are made may be made byeither extrusion or rolling processes. In addition, rods 20 and 20A maybe made from any suitable ferrous material, such as steel, or anysuitable nonferrous material, such as aluminum or materials containingaluminum. Excellent results have been obtained using 6066 aluminumalloys.

In this presentation of the invention the completed slug 30 has in eachinstance been formed using a cooperating punch and die wherein the punchis not received within the cavity carrying the workpiece to be formed;however, it will be appreciated that in some applications it may bedesirable to form slug 30 using an apparatus which uses an internalpunch, i.e., the punch is received within the workpiece cavity.

In this disclosure of the invention the blanks 22 and 22A have beenillustrated and described as being formed in the closed die apparatuspresented in FIGS. 3 and 11 respectively. However, it is to beunderstood that in many applications it may be preferred to use what arepopularly referred to as open die" arrangements, wherein a particularblank is partially formed or upset with associated portions of a formingapparatus engaging opposed ends thereof and with the central portion ofthe particular blank which is arranged between the opposed endsremaining unsupported.

In this presentation of the invention the forming movement of each presshas been shown as a vertical movement; however, it will be appreciatedthat the movement in each instance may be horizontal or at some inclinedangle, if desired.

While present exemplary embodiments of this invention, and methods ofpracticing the same, have been illustrated and described, it will berecognized that this invention may be otherwise variously embodied andpracticed within the scope of the following claims.

What is claimed is:

1. A method of making a slug having an improved grain orientationwherein the individual grains thereof are in substantially parallelrelation, said method comprising the steps of, severing an elongatedwrought rod having a predominant grain direction to define a rod blankhaving a desired weight, supporting said blank on a first formingapparatus, partially forming said blank with said first formingapparatus to define a partially formed blank, placing the partiallyformed blank in an extrusion cavity of a second forming apparatus withits predominant grain direction arranged transverse the direction offorming movement of said second forming apparatus and in a stationaryposition relative to said cavity, and relatively moving a die and acooperating ram of said second forming apparatus against said partiallyformed blank with said blank in its stationary position to define saidslug having the individual grains thereof arranged substantiallyparallel and with the parallel grains being arranged in a directionwhich is perpendicular to the direction of forming movement of saidsecond apparatus, said extrusion cavity having a volume which isslightly greater than the volume of said slug and said step ofrelatively moving comprises the step of impacting said ram and dieforcefully against said partially formed blank causing it to fillpractically the entire volume of said cavity and define said slug whichhas a smooth exterior free of projections, said rod comprising a rod ofsubstantially rectangular crosssectional outline, said severing stepcomprising severing said rod to define said blank having approximatelythe shape of a parallelepiped, said supporting step comprisingsupporting said blank on said first forming apparatus with itspredominant grain direction arranged transverse the direction of formingmovement of said first forming apparatus, said step of partially formingcomprising rounding certain corners of said blank to assure provision ofsaid slug having said smooth exterior surface.

2. A method of making'a slug having an improved grain orientationwherein the individual grains thereof are in substantially parallelrelation, said method comprising the steps of, severing an elongatedwrought rod having a predominant grain direction to define a rod blankhaving a desired weight, supporting said blank on a first formingapparatus, partially forming said blank with said first formingapparatus to define a partially formed blank, placing the partiallyformed blank in an extrusion cavity of a second forming apparatus withits predominant grain direction arranged transverse the direction offorming movement of said second forming apparatus and in a stationaryposition relative to said cavity, and relatively moving a die and acooperating ram of said second fonning apparatus against said partiallyformed blank with said blank in its stationary position to define saidslug having the individual grains thereof arranged substantiallyparallel and with the parallel grains being arranged in a directionwhich is perpendicular to the direction of forming movement of saidsecond apparatus, said extrusion cavity having a volume which isslightly greater than the volume of said slug and said step ofrelatively moving comprises the step of impacting said ram and dieforcefully against said partially formed blank causing it to fillpractically the entire volume of said cavity and define said slug whichhas a smooth exterior free of projections, said rod comprising a rod ofsubstantially circular crosssectional outline, said severing stepcomprising severing said rod to define said blank having approximatelythe shape of a right circular cylinder and having a vertical heightwhich is greater than any dimension of said extrusion cavity of saidsecond fonning apparatus measured in a direction perpendicular to thedirection of forming movement of said second forming apparatus, saidsupporting step comprising supporting said blank with its predominantgrain direction arranged parallel to the direction of forming movementof said first form ing apparatus, said step of partially formingcomprising rounding the corners of said blank and simultaneouslysubstantially reducing said vertical height to enable placing thepartially formed blank in said second forming apparatus with itspredominant grain direction arranged transverse the direction of formingmovement of said second forming apparatus.

1. A method of making a slug having an improved grain orientationwherein the individual grains thereof are in substantially parallelrelation, said method comprising the steps of, severing an elongatedwrought rod having a predominant grain direction to define a rod blankhaving a desired weight, supporting said blank on a first formingapparatus, partially forming said blank with said first formingapparatus to define a partially formed blank, placing the partiallyformed blank in an extrusion cavity of a second forming apparatus withits predominant grain direction arranged transverse the direction offorming movement of said second forming apparatus and in a stationaryposition relative to said cavity, and relatively moving a die and acooperating ram of said second forming apparatus against said partiallyformed blank with said blank in its stationary position to define saidslug having the individual grains thereof arranged substantiallyparallel and with the parallel grains being arranged in a directionwhich is perpendicular to the direction of forming movement of saidsecond apparatus, said extrusion cavity having a volume which isslightly greater than the volume of said slug and said step ofrelatively moving comprises the step of impacting said ram and dieforcefully against said partially formed blank causing it to fillpractically the entire volume of said cavity and define said slug whichhas a smooth exterior free of projections, said rod comprising a rod ofsubstantially rectangular cross-sectional outline, said severing stepcomprising severing said rod to define said blank having approximatelythe shape of a parallelepiped, said supporting step comprisingsupporting said blank on said first forming apparatus with itspredominant grain direction arranged transverse the direction of formingmovement of said first forming apparatus, said step of partially formingcomprising rounding certain corners of said blank to assure provision ofsaid slug having said smooth exterior surface.
 2. A method of making aslug having an improved grain orientation wherein the individual grainsthereof are in substantially parallel relation, said method comprisingthe steps of, severing an elongated wrought rod having a predominantgrain direction to define a rod blank having a desired weight,supporting said blank on a first forming apparatus, partially formingsaid blank with said first forming apparatus to define a partiallyformed blank, placing the partially formed blank in an extrusion cavityof a second forming apparatus with its predominant grain directionarranged transverse the direction of forming movement of said secondforming apparatus and in a stationary position relative to said cavity,and relatively moving a die and a cooperating ram of said second formingapparatus against said partially formed blank with said blank in itsstationary position to define said slug having the individual grainsthereof arranged substantially parallel and with the paralleL grainsbeing arranged in a direction which is perpendicular to the direction offorming movement of said second apparatus, said extrusion cavity havinga volume which is slightly greater than the volume of said slug and saidstep of relatively moving comprises the step of impacting said ram anddie forcefully against said partially formed blank causing it to fillpractically the entire volume of said cavity and define said slug whichhas a smooth exterior free of projections, said rod comprising a rod ofsubstantially circular cross-sectional outline, said severing stepcomprising severing said rod to define said blank having approximatelythe shape of a right circular cylinder and having a vertical heightwhich is greater than any dimension of said extrusion cavity of saidsecond forming apparatus measured in a direction perpendicular to thedirection of forming movement of said second forming apparatus, saidsupporting step comprising supporting said blank with its predominantgrain direction arranged parallel to the direction of forming movementof said first forming apparatus, said step of partially formingcomprising rounding the corners of said blank and simultaneouslysubstantially reducing said vertical height to enable placing thepartially formed blank in said second forming apparatus with itspredominant grain direction arranged transverse the direction of formingmovement of said second forming apparatus.